Cain Velasquez was so dominant champ. Completely destroyed every fighter on sea level, except JDS with that killer instinct, but he took his revenge on him in JDS vs Cain II and III. JJ had problem with Gus and also some problems when he fought against Cormier. Cain is bigger, better, stronger version of Cormier and he also have insane cardio. Jon Jones knows that and he avoided fight against Cain when he was a champ.